The Data Management and Statistics and Community Impact Modeling (DSM) Core constitutes the central resource for all statistical, and management needs. Data generated by each of the other cores and research projects will be transferred to the Database Management Unit for storage in an integrated SIR/DBMS data management system designed to meet all the needs of the Center with respect to cleaning, organization and retrieval of data for planned and ad hoc analyses. These activities will be carried out by a data manager and a data entry clerk working on a networked system of Pentium PCs specifically configured for data management operations, under the direct supervision of the Core Director. The Statistics Unit will be responsible for coordinating the planning and implementation of all analyses conducted by Center research, statistical and programming staff. The proposed research projects have certain features in common that lend themselves tot similar analytic methods. These include a shared prospective cohort, the collection of longitudinal data, interest in change from baseline values, and a combination of dichotomous and continuous variables that defined the asthma and adverse developmental outcome measures. In addition to these traditional core functions, a Community Impact Modeling Unit is included in the DSM core to: (1) provide the research projects with a centralized resource for community-level information; (2) provide expertise in developing quantitative measures of community risk; (3) incorporate these measures into project-specific statistical models to determine whether, after controlling for individual risk factors, adverse health outcomes of children are related to community level risk; (4) determine whether relationships between individual risks and adverse health outcomes vary as a function of community level risk and (5) establish whether the effects of the planned interventions are affected by community level risk.